Hello Jakob!
Another possibility would be to use a LADSPA plugin for the sine wave.
There's the sin_cos plugin from the swh LADSPA plugins. It generates a sine
wave at your desired pitch. It outputs a sine wave of that frequency in the
left channel and a cosine wave in the right channel.
I seem to remember, that there was another plugin in the cmt suite (the
basic plugins released by Richard E. Furse.
You could also use csound, if you still don't get precise results. In csound
you might have something like:
sine.orc
sr = 96000
kr = 9600
ksmps = 10
nchnls = 1

instr 1
a1 oscil 32767, 50, 1
out a1
endin

sine.sco
f1 0 32768 10 1
i1 0 0.02
e

the same result can be achieved with any other synthesizer language of your
choice.
I hope this helps, although not very Ecasound-ish.
Kind regards
Julien

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